Adds async interface method to PersistentPrefStore.

chrome/browser/prefs/overlay_persistent_pref_store.cc

Index: chrome/browser/prefs/overlay_persistent_pref_store.cc
diff --git a/chrome/browser/prefs/overlay_persistent_pref_store.cc b/chrome/browser/prefs/overlay_persistent_pref_store.cc
index e75fbc66b33a72da7e94f61e6d04867f6b903973..9bd1992b10008a1f7b42a184df3419502663d511 100644
--- a/chrome/browser/prefs/overlay_persistent_pref_store.cc
+++ b/chrome/browser/prefs/overlay_persistent_pref_store.cc
@@ -80,9 +80,15 @@ bool OverlayPersistentPrefStore::ReadOnly() const {
 
 PersistentPrefStore::PrefReadError OverlayPersistentPrefStore::ReadPrefs() {
   // We do not read intentionally.
+  OnInitializationCompleted(true);
   return PersistentPrefStore::PREF_READ_ERROR_NONE;
 }
 
+void OverlayPersistentPrefStore::ReadPrefsAsync(ReadErrorDelegate* delegate) {
+  // We do not read intentionally.
+  OnInitializationCompleted(true);
+}
+
 bool OverlayPersistentPrefStore::WritePrefs() {
   // We do not write intentionally.
   return true;
@@ -105,7 +111,7 @@ void OverlayPersistentPrefStore::OnPrefValueChanged(const std::string& key) {
     FOR_EACH_OBSERVER(PrefStore::Observer, observers_, OnPrefValueChanged(key));
 }
 
-void OverlayPersistentPrefStore::OnInitializationCompleted() {
+void OverlayPersistentPrefStore::OnInitializationCompleted(bool succeeded) {
   FOR_EACH_OBSERVER(PrefStore::Observer, observers_,
-                    OnInitializationCompleted());
+                    OnInitializationCompleted(succeeded));
 }